What you see. The starting point for addressing any equine health related issue is your observation.


Seizures or Convulsions (in Adult)


True seizures are a result of abnormal electrical activity in the brain, and are rare in horses. Brain trauma or any disease process that affects the brain can result in seizures. Epilepsy is abnormal brain electrical activity without any underlying cause known. Seizure-like activity can also occur at the end stage of any severe acute disease, i.e. when a horse is dying. The distressed activity of a horse in abdominal pain (colic) is sometimes confused with seizure.

Probably the most common occurrence of seizure follows an attempt at intravenous (IV) injection of a medication. Seizure results from accidental injection of a medication into the carotid artery, which lies immediately deep to the jugular vein and carries blood directly to the brain.

Horses that experience generalized seizures usually fall down on their sides and paddle with their limbs. Their neck is extended rigidly, and their third eyelids cover their eyes. Typically a horse seems unaware of its surroundings, their breathing is labored or shallow, and they may urinate or defecate uncontrollably. In a localized seizure, a particular body part violently or uncontrollably shakes or twitches. Many seizures are short-lived and the horse may get back to its feet. Often, horses are wobbly and weak in the minutes following an episode.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
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your role


What To Do

Most importantly, be very careful. You probably cannot do much to help. Carefully move objects away if it is safe to do so, to prevent the horse contacting those. If your horse is experiencing a seizure and is down on the ground, ALWAYS stay at their back and away from their legs. If you are confident, you may stay at their back and try to comfort them until the vet arrives. Above all be careful! Recognize that any handling of a horse experiencing seizures is dangerous.

NOTE: This observation can be associated with Rabies, which is very rare in horses but does occur. As a precaution, if you must handle the horse, wear gloves.

What Not To Do

Do not attempt to right the horse or help the situation without knowledge of what you are doing. This is a dangerous situation and you could be severely injured.

your vet's role

In most cases, your vet will try to control the seizures with medication while trying to perform the diagnostics necessary to determine a cause. The cause will determine prognosis.
Questions Your Vet Might Ask:
  • Did your horse fall down?
  • Describe exactly what you are seeing?
  • Was the horse recently given a penicillin shot?
  • Did you try to give the horse an intravenous injection?
  • To you knowledge, did your horse have an accident or injure itself lately?
  • Have you noticed this happen before?
  • What is the horse's age, sex, breed and history?
  • Can I have your location and directions to get to you as soon as possible?
  • Have you noticed the horse showing any behavioral changes?
  • Has anything changed in the environment, feed or management?
  • Has the horse had any other signs of a problem?
  • When was the horse injected?
  • Does your horse seem aware and alert?
  • Has the horse received any medications or new feeds or supplements?
  • What are the results of the Whole Horse Exam (WHE)?

Diagnostics Your Vet May Perform

Figuring out the cause of the problem. These are tests or procedures used by your vet to determine what’s wrong.

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Diagnoses Your Vet May Consider

The cause of the problem. These are conditions or ailments that are the cause of the observations you make.

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Author: Doug Thal DVM Dipl. ABVP